-project settings are saved when changed

-load() was in the GDScript docs but missing in the scripting-different music for platformer 2D and 3D
-fix how documentation is generated, built in doc browser should be always up to date
-copypaste, scrolling, etc in  builtin doc
-built-in scripts get saved now (though debugger may not always work on them)
-Theme can be set to controls as a property

tools/doc/doc_data.h

@@ -32,6 +32,7 @@
 
 #include "variant.h"
 #include "map.h"
+#include "io/xml_parser.h"
 
 class DocData  {
 public:
@@ -82,6 +83,8 @@ public:
 	String version;
 
 	Map<String,ClassDoc> class_list;
+	Error _load(Ref<XMLParser> parser);
+
 
 public:
 
@@ -90,7 +93,6 @@ public:
 	Error load(const String& p_path);
 	Error save(const String& p_path);
 
-	Error save_compressed_header(const String& p_path);
 	Error load_compressed(const uint8_t *p_data, int p_compressed_size, int p_uncompressed_size);